FBI Director James Comey confirmed that bureau investigators were looking into whether Donald Trump’s presidential campaign colluded with Moscow during the 2016 election.

The FBI chief made the disclosure in his opening statement Monday morning before the House Intelligence Committee, which is looking into Russian interference in the election, leaks of classified information and charges by the president that his campaign was wiretapped by President Barack Obama. Comey noted that the FBI customarily does not confirm ongoing investigations — especially those concerning classified matters — but it may be appropriate to do that, as the Justice Department (DOJ) recognizes, if it is in the public’s interest.

“I have been authorized by the Department of Justice to confirm that the FBI, as part of our counterintelligence mission, is investigating the Russian government’s efforts to interfere in the 2016 presidential election,” he said. “And that includes investigating the nature of any links between any individuals associated with the Trump campaign and the Russian government, and whether there was any coordination between the campaign and Russia’s efforts.”

The probe will also look into whether any crimes were committed.

Comey noted that the FBI had already taken the “extraordinary step” — at the request of congressional leaders — of briefing members of Congress, including leaders of the committee, on the investigation in detail. He said that he could not elaborate further on the nature of the probe because it is ongoing and classified, acknowledging that this may be frustrating to some.

“The FBI is very careful in how we handle information about our cases and about the people we are investigating,” he continued. “We are also very careful about the way we handle information that may be of interest to our foreign adversaries. Both of those interests are at issue in a counterintelligence investigation.”

Comey urged the committee not to draw unfounded conclusions from the fact that he may not be able to comment on particular topics. He said that the FBI and the DOJ have provided more thorough information during past testimonies but that these regarded completed investigations — a key difference.

“I know speculating is part of human nature, but it really isn’t fair to draw conclusions simply because I say that I can’t comment,” he said.

According to Comey, the FBI needs to exercise great caution so it does not compromise the privacy of any individuals involved, inadvertently divulge clues about where it is going or tip off foreign adversaries about its actions. He could not provide a timetable for when the investigation would be completed but promised it would be conducted in a open-minded and independent manner.